Sometimes while making a digital scrapbook layout, I find myself needing a "paper" of a certain color. For what? Oh, a piece of white to use as vellum or a piece of white to put underneath a paper I'm going to change the opacity on (it brightens up a dark paper and mellows a too-bright color or pattern once the opacity is tweaked). A lot of times a designer has created an amazing piece of patterned paper but doesn't give you the solid papers in the kit to match all the colors you might use. So you can just create your own! And even better, slight variations of the color to suit your purpose! I don't really get using fill layers (maybe someday!) But this way of doing it is pretty easy, so it's all good. ;o)
Here's what I do:
1. First, I guess you need to have an idea of the color you want. Otherwise how are you going to know when you get it right?
2. Next, you need to decide what size you think you'll need your new "paper" to be. Better to over-estimate than under. A lot of times I just create whatever size my layout is, then cut and paste (well, select, drag, and drop) what I need.
3. Remember our friend the color dropper? Most likely the color you want is on your layout already. In this example I'm going to use this gorgeous green and blue paper by Shabby Princess from her "Splash" kit. In the kit, she has provided a solid of the green and the light blue, but not the darker blue. (I really like using the dark colors from patterned papers for contrast.) So I select the color dropper, put it over the dark blue that I like, and click. (You may want to use the zoom tool to enlarge the area you're selecting from for extra precision.) [the screen shot wouldn't show where I had the actual eye-dropper positioned, so I put a red circle around it for you.] Once I've clicked my dark blue area, you'll see that the foreground color (blue square above the red square just below the color dropper) has turned to the blue color I selected.
4. If I need to make an adjustment, I can use this color as a starting point for a lighter or darker color that will still be in the same color family and fit in with the layout. Clicking once on the now blue foreground box brings up this Color Picker options box. There is a light circle in the middle that shows me which color is currently picked as foreground. Putting my mouse within that box with all the shades of blue allows me to select another shade of the color. If you position your mouse directly above the current shade and click, you choose a lighter share. Directly below chooses a darker one. The selection doesn't actually change until you hit ok, but you see a preview in the box to the left of the "OK" button.
5. Now (out of the Color Picker options and back to the normal Photoshop screen), you need to switch this newly selected Foreground to Background. The bent arrows above the foreground/background (blue/red) boxes in the toolbar accomplishes this.
6. Create a new file ("File > New" or "Ctrl" + "N"). Select your dimensions and resolution, then at the bottom your "Contents" choices are "White," "Background Color," or "Transparent." Here I choose "Background Color," hit "ok," and I get my new blue solid colored paper. Good to go!
I have yet to master cool texture effects for paper like this, but here is a quick way to make this file look more like paper than a random new color on the computer: in the file menu, choose "Filter > Texture > Texturizer." Then play with the settings and hit "ok."